MuscleNerd has announced a major update to the RedSn0w jailbreak utility that brings numerous new features.

Changelog:
- uses DFU mode to try to automatically determine which device and FW you have
fetches pieces of public IPSWs from Apple (once). Non-public IPSWs must be provided manually (once). It then caches those pieces for future use.
- "Just boot" is a tethered boot. Uses whatever "Preferences" you've set for boot logo and kernel boot-args
- "Pwned DFU" puts your device in a pwned DFU state for some of the iTunes stuff detailed below
- "Recovery fix" gets past 1015 types of errors (when baseband portion of restore fails). Should work on iOS5 beta too
- "Select IPSW" is for picking non-public IPSWs, or overriding auto-detection
- "SHSH blobs" has a bunch of options…
- "Fetch" - fetch current PARTIAL blobs on device. Puts this set PARTIAL of blobs on your computer as a plist. Checks if Cydia already has a full set for this device and build. If not, it submits this partial set and returns Cydia's acknowledgement or rejection
- "Verify" - cryptographically verifies existing blob files from either redsn0w, TinyUmbrella, or Cydia server. You can select a whole bunch of blobs to verify at once if you want (like the TinyUmbrella directory)
- "Submit" - both verifies and submits one or more blob files to Cydia. This lets you copy your entire TinyUmbrella cache of blobs up to the Cydia server
- "Query" - queries the Cydia server for all available full or partial blobs for a given set of ECIDs
- "Stitch" - stitches either FULL or PARTIAL blobs to a STOCK or CUSTOM IPSW

1. FULL blobs stitched to a STOCK IPSW gives you a completely self-contained signed IPSW that iTunes will accept without any tricks (no need to go into pwned DFU mode, no need to start TinyUmbrella TSS server, no need to redirect to Cydia server for blobs)
2. PARTIAL blobs stitched to any IPSW requires you to go into pwned DFU mode before running iTunes. No need to start TU or use Cydia though.
3. stitching either FULL or PARTIAL blobs to a CUSTOM IPSW also requires a pwned DFU start before iTunes restores. No need to start TU or use Cydia though.
4. stitching is NOT yet supported on iPhones (well, at least not tested). Need to work out the baseband part of the restore process.
5. will eventually support fetching the blobs directly from Cydia instead of a file on your computer